View Poll Results: Did you regear for 35's?
Yes
37
29.13%
No
90
70.87%
Voters: 127. You may not vote on this poll
35's with or without regearing
JK Junkie
Joined: May 2009
Posts: 3,074
Likes: 1
From: Denton, TX
For the added fuel consumption as well as the trans being under load more than normal...everywhere you go. I'd think more people would regear. I couldn't imagine 3.21s and 35s, or even 3.73s. It's comparable to towing, oh probably 800lb trailer every where you go. Not much, but to drag it around all the time is just pointless. Your trans would appreciate it (auto guys), clutch for the sticks.
JK Freak
Joined: Mar 2008
Posts: 783
Likes: 3
From: Southeast
I've got 35s on heavy Hutchinson rims with the 6-speed and 4.10 stock Rubicon gears on a pretty heavy 2 door (full bumpers, aux lights, spare, winch, skids, suspension, recovery gear, CO2 tanks).
My Jeep was close, but it wasn't until I added the SC Flashpaq that it actually became acceptable to me peformance wise. I have to do a bit of cruising at 80mph interstate speeds, and for the terrain around here (eastern Georgia) the Flashpaq actually made the difference I needed. Particularly in the 2 lane secondary road scenario, where you have to pass a car doing 55mph, safely.
Just today, with the newest 93 tune and premium fuel, I was actually able to gain velocity uphill at 80mph (2850rpm) in a Jeep that formerly wouldn't have held speed in 5th! The programmer isn't a substitute for gears, but if you're close it might just do the trick.
I plan on either 4.88 or even 5.13 gears. Generally my interstate runs aren't long, and 45 minutes at 3400 rpm isn't going to hurt anything except mileage. I've got to decide whether it'll be 37s or not in the future, but I'm leaning strong toward staying with the 35s, so 4.88s will probably be it. Then, an Atlas 4 speed transfer case will be in my sights.
We have to be honest with ourselves about something as significant as a gear change.
For instance, why go with the most lift and tallest tires if you're not really planning on rock climbing. My Jeep is more of an all purpose trail runner/rescue rig. I plan on staying the course, adding in the strongest axles, toughening up the 44 front, going to a dual battery system, completing the skid plates, getting a set of OEM half doors, installing an belt driven onboard compressor/tank, the Atlas, a dedicated mobile HAM rig (IC7000/antenna) and even a rear winch.
Sure I coukld score more points on these forums and at the mall with a set of Xenon fenders, more lift, and some 40" Toyos MTs. Just don't call me if you get stuck!
My Jeep was close, but it wasn't until I added the SC Flashpaq that it actually became acceptable to me peformance wise. I have to do a bit of cruising at 80mph interstate speeds, and for the terrain around here (eastern Georgia) the Flashpaq actually made the difference I needed. Particularly in the 2 lane secondary road scenario, where you have to pass a car doing 55mph, safely.
Just today, with the newest 93 tune and premium fuel, I was actually able to gain velocity uphill at 80mph (2850rpm) in a Jeep that formerly wouldn't have held speed in 5th! The programmer isn't a substitute for gears, but if you're close it might just do the trick.
I plan on either 4.88 or even 5.13 gears. Generally my interstate runs aren't long, and 45 minutes at 3400 rpm isn't going to hurt anything except mileage. I've got to decide whether it'll be 37s or not in the future, but I'm leaning strong toward staying with the 35s, so 4.88s will probably be it. Then, an Atlas 4 speed transfer case will be in my sights.
We have to be honest with ourselves about something as significant as a gear change.
For instance, why go with the most lift and tallest tires if you're not really planning on rock climbing. My Jeep is more of an all purpose trail runner/rescue rig. I plan on staying the course, adding in the strongest axles, toughening up the 44 front, going to a dual battery system, completing the skid plates, getting a set of OEM half doors, installing an belt driven onboard compressor/tank, the Atlas, a dedicated mobile HAM rig (IC7000/antenna) and even a rear winch.
Sure I coukld score more points on these forums and at the mall with a set of Xenon fenders, more lift, and some 40" Toyos MTs. Just don't call me if you get stuck!
JK Newbie
Joined: Nov 2008
Posts: 81
Likes: 0
From: WA
Running 35's on our rubicon (4.10s) and we did NOT regear. Will I regear eventually??? eh, probably, but it's really low on the priority list. I can spend that kind of cash on other things that will make my rig more trail capable. I know regearing gives you a better crawl ration and does help on the trail but I feel like mostly the reason for regearing is onroad performance.
JK Enthusiast
Joined: Apr 2009
Posts: 313
Likes: 0
From: San Antonio, TX
I'm not so sure I agree with that chart either.
I have a an 2009 unlimited X with 35x 13.50x18's on chrome pro comp 6001s with stock gears (3.73, I'm assuming).. and I have no problem hauling 70-80 on the interstate. Don't get me wrong.. It's doesn't have crazy power or anything.. but I wouldn't say that it was sluggish.
Am I misreading the chart or is it saying that for optimal (Green zone) tire size with auto and factory gears is.. 27-28 inch tire??
I have a an 2009 unlimited X with 35x 13.50x18's on chrome pro comp 6001s with stock gears (3.73, I'm assuming).. and I have no problem hauling 70-80 on the interstate. Don't get me wrong.. It's doesn't have crazy power or anything.. but I wouldn't say that it was sluggish.
Am I misreading the chart or is it saying that for optimal (Green zone) tire size with auto and factory gears is.. 27-28 inch tire??
JK Super Freak
Joined: Aug 2008
Posts: 1,799
Likes: 1
From: Seattle, WA
I have been running stock gears (3.73) with 35X13.5 tire and have'nt had any issues. It really depends on driving habits, and where they drive. I live in the city where it's really a non issue. Even when I make long road trips, it isn't all that bad. I will regear at some point though
-
Joined: Jul 2009
Posts: 229
Likes: 0
From: Mascouche, Qc
I have my 35" X 12.5" for 2 months and did pretty good trails with them, and I see no lack of power. Its the 4 doors automatic tran. Only once, going back home with pressure at 22 in tires was it not on OD at 70mph with a good wind in front.
Its a Jeep Rubicon, not a Mustang... I don't expect the big acceleration, but it does go over that big big rock on the trail and up that very steep hill, hey, that's what I expect from my Jeep !!!
No re-gearing for me !!
Its a Jeep Rubicon, not a Mustang... I don't expect the big acceleration, but it does go over that big big rock on the trail and up that very steep hill, hey, that's what I expect from my Jeep !!!
No re-gearing for me !!
Last edited by jk20084p; Aug 27, 2009 at 02:57 AM.
JK Junkie
Joined: May 2009
Posts: 3,074
Likes: 1
From: Denton, TX
JK Junkie
Joined: May 2009
Posts: 3,074
Likes: 1
From: Denton, TX
You know what. You are right. That is a flaw. Instead of Tire Size, it should clarify actual measured tire height mounted and installed on the vehicle.
We'll have to ask Jpop adjust his chart with a clarification regarding actual height.
According to Toyo: h ttp://marktg.toyotires.com/file/18136.pdf
His tires are 34.8" tall when unmounted and brand new.
When the tire is mounted to a wheel and installed on your rig, it is impossible to keep that same height.
It depends on the width of your wheel, the psi you run, and the weight of the vehicle.
If you run a reasonable psi so as to not have an overly stiff ride, and if you are running a 8-9" wheel, you probably loose about 1.5" when the tire is mounted and installed (you can see some of it in the bulge).
Then, as your tire wears down, your height goes down.
To measure the actual mounted and balanced height of your tire, you can use a measuring tape from the floor up to the top outside edge of your tire. If you are using a different number with your speedometer programmer, your odometer, speedometer, gas mileage, and gas mileage range will be incorrect. For example, if you install a 34.8" tire that nets 33.25" after it is mounted and installed on your rig, and you put 35" in your Superchips/AEV ProCal/Hypertech/Accupro, your rig is overstating your mpg, odometer, and speed.
I'd bet if you measured your Stock Rubi tires, they are not 32.1" tall.
We'll have to ask Jpop adjust his chart with a clarification regarding actual height.
According to Toyo: h ttp://marktg.toyotires.com/file/18136.pdf
His tires are 34.8" tall when unmounted and brand new.
When the tire is mounted to a wheel and installed on your rig, it is impossible to keep that same height.
It depends on the width of your wheel, the psi you run, and the weight of the vehicle.
If you run a reasonable psi so as to not have an overly stiff ride, and if you are running a 8-9" wheel, you probably loose about 1.5" when the tire is mounted and installed (you can see some of it in the bulge).
Then, as your tire wears down, your height goes down.
To measure the actual mounted and balanced height of your tire, you can use a measuring tape from the floor up to the top outside edge of your tire. If you are using a different number with your speedometer programmer, your odometer, speedometer, gas mileage, and gas mileage range will be incorrect. For example, if you install a 34.8" tire that nets 33.25" after it is mounted and installed on your rig, and you put 35" in your Superchips/AEV ProCal/Hypertech/Accupro, your rig is overstating your mpg, odometer, and speed.
I'd bet if you measured your Stock Rubi tires, they are not 32.1" tall.
That i understand. But you can almost just throw that theory out the window since all 35s will be about there. All 33s will be about there. So it's an even playing field throughout all the tire sizes. Until to go to specific RPM. I may be curious to measure my Rubi tires just for the hell of it. Friend of mine just bought some 35" KM2s and I'd like to measure those as well. Just for kicks. But with your theory, a 33 would be a "31" once installed. So the same difference is going to be there with the rest...
